Machine readable images in the form of a QR code represent either a URL, text, an SMS message to be sent, a product number, an inventory code, an expiration date or a phone number to be called. This machine readable image is captured by a device comprising a capturing device. Examples of such devices are mobile phones, handheld scanners, organizers, photo and video cameras, tablets, terminals, computing devices, and MP3 players. Formerly confined to industrial uses, they have in recent years become common in consumer advertising and packaging, because the dissemination of smart phones “has put a barcode reader in everyone's pocket” for the first time. As a result, the QR code has become a focus of advertising strategy, since it provides quick and effortless access to the brand's website.
Many of these applications target mobile phone users (via mobile tagging). Users may receive text, add a vCard contact to their device, open a Uniform Resource Identifier (URI), or compose an e-mail or text message after capturing QR Codes. They can generate and print their own QR Codes for others to capture and use by visiting one of several pay or free QR Code-generating sites or apps. Apps for capturing QR Codes can be found on nearly all smart phone devices.
QR Codes storing addresses and Uniform Resource Locators (URLs) appear in magazines, on signs, on buses, on business cards, or on almost any object about which users might need information. Users with a camera phone equipped with the correct reader application can capture the image of the QR Code to display text, contact information, connect to a wireless network, or open a web page in the telephone's browser. This act of linking from physical world objects is termed hardlinking or object hyperlinking. QR Codes may also be linked to a location to track where a code has been captured. Either the application that scans the QR Code retrieves the geo information by using GPS and cell tower triangulation or the URL encoded in the QR Code itself is associated with a location.
The QR code is readable from any direction in 360°. QR Code is capable of 360 degree (omni-directional), high speed reading. QR Code accomplishes this task through position detection patterns located at three corners of the symbol. These position detection patterns guarantee stable high-speed reading, circumventing the negative effects of background interference.
Custom or artistic QR codes are standard QR codes that have been modified for aesthetic purposes or to make it easier for people to recognize a brand. Many companies use different design techniques to help their code stand out among the crowd. These techniques include: adding color, shapes and various techniques such as round or pointed edges.
U.S. Pat. No. 5,726,435 discloses a 2 dimensional machine readable code, a so called 2D barcode. To properly decode the information stored in the 2D Barcode U.S. Pat. No. 5,726,435 discloses in FIG. 3 and the associated description an apex detection to determine the actual tilt angle of the 2D barcode.
The teaching of how to obtain this apex and thus the tilt angle of the 2D barcode provided in U.S. Pat. No. 5,726,435 is incorporated by reference. Many other methods of determining a tilt angle of an object in general are known and can be applied. Common to all these methods, including the one disclosed in U.S. Pat. No. 5,726,435 is that in order to correct the rotational offset the tilt angle must be determined before applying the correction in order to obtain a proper upright version of the 2D barcode before commencing the decoding process.
The decode preprocessing includes tilt angle detection and coordinate conversion processing, both of which are mandatory when each two-dimensional code is randomly placed with an uncertain tilt angle with respect to a reading device.
Machine readable codes are associated with either a URL, text, an SMS message to be sent or a phone number to be called. The URL, text, SMS message including the destination or the telephone number are obtained by decoding the machine readable code. The machine readable codes such as 2 dimensional codes have a fixed, limited amount of data that can be stored in them. Consequently only a single URL, text, SMS message or phone number is currently stored in the machine readable codes. This results in multiple Machine readable codes having to be used when multiple items relating to a single article are to be conferred to the user.
For instance a television set advertisement may have a machine readable code comprising a URL pointing to a web site with more details (specifications, images) of the television set than the advertisement can provide in the limited space. An additional machine readable code is required to provide a URL for the user manual or to locate a dealer.